In the filing obtained by ET, Daniels calls Penn’s lawsuit "an assault on the First Amendment."
"With fame, money and high-priced legal counsel, Penn has the power to buy most things," the documents read. "Fortunately for Daniels, the First Amendment is not for sale. It protects Daniels and others from lawsuits like this one, financially-draining attacks brought to punish free speech exercised to Penn’s chagrin."
Penn, 55, filed the defamation suit in September, claiming that 55-year-old Daniels made "false and defamatory statements" about him in an interview where the producer brought up Penn while discussing Terrence Howard's history of domestic violence abuse.
"[Terrence] ain't done nothing different than Marlon Brando or Sean Penn, and all of a sudden he's some f***in' demon... That's a sign of the times, of race, of where we are right now in America," The Hollywood Reporter quoted Daniels as saying.
In the Dec. 3 filing, Daniels says Penn's lawsuit is "a blunt force instrument wielded in an attempt to control the narrative of his life" and calls upon the actor to prove the statement is defamatory.
"While Penn may have personally experienced the challenged statement as offensive, he must now demonstrate that the statement is reasonably susceptible to a defamatory meaning. He has not, and cannot," the documents read. "The challenged statement is constitutionally protected opinion, and New York courts have repeatedly emphasized the need to summarily reject defamation claims brought to bully those who dare exercise their constitutional right of free speech."
Daniels is represented by James Sammataro of Stroock & Stroock & Lavan
Penn's initial lawsuit read: "Daniels has falsely asserted and/or implied that Penn is guilty of ongoing, continuous violence against women." The doc goes on to state: "...while [Penn] has certainly had several brushes with the law, Penn (unlike Howard) has never been arrested, much less convicted, for domestic violence, as his ex-wives (including Madonna) would confirm and attest."
Daniels has declined to comment on the suit, but in October, his lawyers responded by asking that the case be moved from the State Supreme Court of New York to a federal district court. The request was due to the fact that Daniels lives in New York and Penn lives in California, and the amount of the lawsuit -- $10 million in damages -- qualifies the case to be heard in a federal court.
However, in November, Daniels withdrew his Notice of Removal and agreed to pay Penn's legal fees.
Penn's lawyer, Mathew Rosengart, told ET in September that the Gangster Squad star has "been subjected to false and baseless attacks for years."
"This is only the most recent example," Rosengart said about Daniels' comments. "As asserted in the lawsuit, there are important issues at stake, including the malicious and reckless repetition of rumors and innuendo at the expense of others."
Penn was married to Madonna from 1985-1989, during which time -- and years later -- tabloids would speculate on alleged troubles in their relationship. Penn did serve 33 days in jail in 1987 for assaulting a photographer.
Although these days, Madonna and Penn are clearly on good terms. In October, the Oscar-winning actor was seen gazing adoringly at his ex-wife from the front row of her concert in Vancouver, Canada. Watch below: